The present invention relates to the field of micro-mechanical switching converters using micro-mechanical transducers. Micro-mechanical switching circuits provide many applications such as voltage converters, switching regulators, phase matching, etc. Mechanical and electronic switching circuits are widely used and micro-mechanical switching circuits can additionally be complimented with traditional switching devices.
MEMS switching converters are known in the art. The many benefits of a MEMS implementation for switching converters include; no voltage loss due to p-n junction, low ohm losses, radiation resistance, ability to convert voltage up and down, prolonged operation using hermetic seal with He gas, prolonged operation using Ir contacts, ability to charge all capacitors simultaneously or based on charge transfer, only simple vibrations necessary to drive the circuits, need for two power supplies for some converters. In the art, large surface area, low tolerance valued capacitors, such as topological capacitors, are integrated to realize these MEMS switching converters.
A prior art switching circuit configuration is illustrated with reference to FIG. 1. FIG. 1(a) illustrates a parallel-series converter as is known in the art. In this embodiment, the input and the output voltages are 1.5V and 12V, respectively. FIG. 1(b) illustrates a charge transfer converter as is known in the art which also has an input voltage of 1.5V and an output voltage of 12V. With reference to FIG. 2, in these embodiments, the required capacitor value for the charge transfer converter, operating frequency 1 kHz at 10% ripple, will be 1.5 nF to realize 12V from a 1.5V supply. In these prior art embodiments, solid-state switches are employed, such as transistors or diodes.
In a thermally activated cantilever switch, a low driving voltage source is required. However, with a low driving voltage source, the operating frequency of the cantilever switch is low. While the heating process for the thermal activation is relatively fast, the cooling process is relatively slow. As such, the overall switching operation frequency for the thermal activated cantilever remains low thereby limiting the use of MEMS switches in high frequency applications
Accordingly, what is needed in the art is a MEMS switch that is operable at a high frequency while also utilizing a low voltage driving source. As such, it would be advantageous in the art to have an efficient DC to DC high voltage converter that requires only simple vibrations to drive the circuits.